Similar Questions

• Align the two signals and measure the Phase Shift

  Hello

  I do an experiment in which I use the NI USB-6221 DAQ card. The jury is able to make 250 k samples/second. I want to measure two voltages in a circuit and find the phase shift between them at frequencies between 1 and 10000. First I ouputted a wave sinusoidal frequency variable through the Commission and applied to a test circuit. Then I used the Board to measure the two tensions consecutively (thus reducing the maximum sampling frequency at 125 k). I used the signals align VI and measured the two phases and then calculates the phase shift (VI attached in Phase 1). It worked well for the test circuit I built in which the phase shift went way logarithmique.20 degrees ~84.5 degrees and then stabilized. At frequencies above 5 000 Hz phase shift must have remained constant, but it varies more or less 1 degree. When the phase shift is 84.5 degrees, present a degree of variability is not particularly explicit. When I asked my program on the circuit that I really wanted to measure, the phase shift went from-. 5 degrees up to about 1.2 degrees. The change in the values of phase shift at high frequencies (> 3000) was environ.2 degrees. Given the small phase shift, this variation is unacceptable. Now I tried to use a sequence to each blood individually (increase the maximum sampling frequency to 250 k) and then align the two signals and measure the phase of each shift. When I use align it and re - sample Express VI to realign the two signals, I get the message "error 20333 analysis: cannot align two waveforms with dt even if their samples are not clocked in phase." Is it possible to align two signals I describe here? I enclose the new VI as Phase 2

  Matthew,

  I think I have an idea for at least part of the problem.

  I took your program data and deleted stuff DAQ.  I have converted the Signal on the chart control and looked then what was going on with the signal analysis.

  The output of the Waveforms.vi line has two waveforms, like the entry.  However, arrays of Y in the two waveforms are empty!  It does not generate an error. After some head scratching, reading the help files and try things out, that's what I think is happening: the time t0 two input signals are 1,031 seconds apart. Since the wavefoms contains 1,000 seconds of data, there is no overlap and may not align them.

  I changed the t0 on two waveforms are the same, and it lines up.  The number of items in the tables is reduced by one. Then I increased the t0 of 0.1 seconds on the first element. The output had both greater than the entry by dt t0 t0 and the size of the arrays was 224998.  Reversing the t0 two elements shifts the phase in the opposite direction.

  What that tells me, is that you can not reliably align two waveforms which do not overlap.

  I suggest that you go to 2-channel data acquisition and that it accept the reduced sample rate.  You won't get the resolution you want, but you should be able to tell if something important happens.

  You may be able to improve the equivalent resolution by taking multiple steps with a slight phase shift. This is similar to the way that old oscilloscopes of sampling (analog) worked. Take a series of measures with the signal you are currently using.  The make enough average to minimize changes due to noise. Then pass the phase of the signal of excitement to an amount that is smaller than the resolution of phase of sampling rate and repeat the measurements.  Recall that I calculated that for a 5 kHz signal sampled at 125kHz, you get a sample every 14.4 degrees. If shift you the phase of 1 degree (to the point/mathematical simulation), you get a different set of samples for excitement.  They are always separated by 14.4 degrees.  Take another series of measures. Transfer phase another degree and repeat.  As long as your sampling clocks are stable enough so that frequency does not drift significantly (and it shouldn't with your equipment), you should be able to get near resolution of what you need.  The trade-off is that you need to perform more measurements and may need to keep track of the phase shifts between the various measures.

  Lynn

• Time scale does not properly after separation of the two signals of virtual channel

  Hi all

  I have a problem when I use a virtual channel with two analog inputs. I'm cutting the two signals into two separate tables of waveform, as shown in the attachment. The two signals seem to be reading very well, the problem is that the time scale (x-axis) begins to act on the strange. Seconds displayed time seems to keep jumping up and down at a high frequency, resulting in the two signals of displayed does not correctly in the table of waveform. Could someone please try to help me? Any help would be greatly appreciated!

  Thanks in advance.

  Try to acquire a signal with first time information. You can replace the DBL 2D with a data type of 1 d wave. You don't need this code extra silly - just a function of Board Index to get the separate channels.

• 200560 error during the generation of the two signals of AO

  Hello

  I am trying to send out two signals and I get error 200560 to "wait until done" vi.

  I was wondering if there is no solution for this problem.

  BTW, the vi is attached.

  Thank you

  Pooya

  You have your clock set to continuous samples. I don't know if you can use 'Wait until what' If you the task will never happen. Set your click on over and see what happens.

• Count the edges of the 2 signals TTL (Heidenhain linear scale)

  Hi all

  This is my first post here. :-)

  Currently, I'm doing a VI to be used with a linear scale. The linear scale gives 2 TTL signals that have an offset of 90 °. The change in distance of the linear scale is given by counting the fronts and edges of the two signals. See the following image: Ua1 is signal 1 and signal 2 Ua2. You can ignore the other signals.

  

  Now, I want to count the 4 edges in order to translate the 2 signals in the distance. This means that I need advanced two counters for Rising-rising, Rising-Falling Falling Falling, falling on the rise for 2 signals. I tried to do 4 points two counters in LabVIEW but that of course does not work, because an acquisition of data can access the card TTL or I did it wrong.

  Once I have to handle this, I also want to understand the meaning.

  My card TTL: NI 9402

  My electronic Heidenhain interface: 100 IBV (http://www.heidenhain.com/fileadmin/pdb/media/img/598_160-23.pdf - also at the origin of the image)

  Hardware configuration: linear scale-> IBV (Elektronic Interface)-> NI 9402-> LabVIEW

  Signals: Analog 3-> 3 TTL-> OR 9402

  I hope I do not double post. Any help would be greatly appreciated.

  I used Heidenhain linear scales in many applications.

  As stated in the previous post, the output of your balance is as a quadrature encoder. Therefore, you must use an entry of the DAQ card counter to measure the position of the scale.

  The desired X 4 mode is done by the meter itself (not possible with some old maps of OR).

  As starting point, see measure angular Position.vi that comes with examples of LabVIEW. On your linear scale, change the type of the polymorphic DAQmx create channel VI CI linear encoder and etiquette of pulses per revolution at a Distance by pulse.

  Feel free to post back if you need further assistance.

• Cross spectral power and consistency of the 2 signals

  Hello

  I try to get the cross-spectral power and consistency of the two signals. I should be able to get this:

  "The cross-spectral power and consistency of these 2 signals have been calculated on a window (8.5 minutes) 1024-sample using the fast Fourier transform applied to the 3 overlapping of the panes of 512-sample in the window of 1024 consistency." In each pane, the data were the first linear straightened and with windows by using the Hanning (cosine) function before the calculation of the Fourier transform. The 1024 coherence window was so advanced by 256 samples (2.1 minutes), and the calculation repeated until all BDUS/interval of N - N series have been analyzed.

  We used the product of consistency and the cross-spectral energy to weight these 2 effects in order to quantify the degree of the hitch.

  I should get this chart type

  

  The RR signal I straightened before that trying to get the power crossed with sampling freq = 2. And I put 2 ways to get it.

  consistency too and later the product of the two. Im trying to get the spectrogram and watch later 3d like picture.

  I have attached the vi.

  Consistency is perhaps badly fixed.

  Thanks for the help, guys.

  Kind regards.

  you made a few mistakes, example en by overhauling it you can't do the segments overlap, that's why you should go with a loop and the creation of a subset (and this is why I suggested para window ASD)

  You must also set the indexing of the product release and do not concatenate, penny you released 2d end that you can use for 3d graphics

  FS in the mathscipt should also be in hz, not in seconds, I told you the last time (he is shown in the help)

• Add two signals different dt

  Hi, I try to achieve the function Sum (+) and Sub (-) with the participation of waveforms, I know the problem and the different dt when dt is the same the smooth executing operations but I want to achieve something like this Waveform sum Figure 1 as you can see if two signals with different frequencies are added between them the result looks like Figure 1 , but with the same dt different frequency is not calculated and the amount always show that the two signals have the same frequency. How can I realize the amount similar to that in Figure 1? Thank you all

  Hello Silversky,

  It seems you want to do something like that...

  But the figure referenced never mentions the signals with different dt! Simply to create waveforms with same dt in the first place...

• How can I synchronize two signals in Labview?

  The first signal is a pulse index which gives the position of a reference point of the wheel (= 1 for 0 ° and signal = 0 for 1-360 °), and the second signal gives the total force meeting the wheel. The two signals have different sampling rates high. The first signal is always 360/rotation, but the second signal varies from cycle to cycle based on how fast the force is changing. The signals are in the form of two columns of numbers in an excel spreadsheet.

  I would like to do such as Labview at the exit of the angular position of the reference at the time of the cycle where the wheel knows the maximum strength in degrees. Can anyone suggest a vi or a method that I might be able to use for this task? I am new to Labview, so any help is appreciated.

  Hi Westerman,

  I have a little trouble to understand the basics of what you're trying to do. A little more details would be very helpful pointing you in the right direction. If you want to align the timestamps/reference of the two signals time?

  I've included a link to a document that describes generally how encoders (I guess that your pulse index indicates that you are using an incremental encoder) can be used in LabVIEW.

  http://www.NI.com/white-paper/7109/en

  You should also try the search the forums for questions relating to the use of a rotary encoder in LabVIEW. I was able to find several with the included code example.

  Feel free to provide us with a few details and we'll help guide you.

  Andy C.

  Technical sales engineer

  National Instruments

• How to specify the spacing between the two components

  Can specify us the distance between two points on a form? If so, please let us know how?
  
  Published by: user1670125 on July 14, 2010 05:37

  Hello user1670125 (please tell us your name).

  It depends on if you mean vertical (distance between the items on separate lines) or horizontal (distance between the items on the same line).

  A method I use for opening a vertical space between two elements is:

  -establish a single display without label
  -Name it "P #_BLANK ' or ' P #_BLANKn ' (if there is more than one page)
  -give a sequence so that it renders between the two points
  -do not escape special characters
  -give a source value of "< br / > < br / > < br / >" (according to the number of blank lines you need)

  A method I use for opening space horizontally between two elements (assumption here, is that you have defined the second element to not display on a new line and have adjusted the scope of column on other points in the same region to bring together the two fields as needed) - simply specify "& nbsp;" & nbsp; & nbsp; "in the first element display text of item (according to the number of spaces you need to).

  Hope this helps,
  John

• Convert stereo mono and play in the two lanes

  I use a stereo to mono plug to convert the sound coming out of my rear jack Mono in the hope of getting the full signal (left and right channels) for play in each speaker stereo. When you use the form, I receive his mono out of the left speaker only and no sound from the right speaker.

  I tried two different stereo to mono converters and do not think that is the problem.
  I know that I can't simply mono audio in Win7 (wtf, btw?) and my integrated sound card does not either mono output.
  Background: I am deaf in my left ear and needed a solution to this for the games while wearing a helmet. In the games that I play, the sound is directional (playback of sounds generated in the left channel to the left of your character) who, being deaf in one ear, I do not. The games allow either for conversion to mono output.
  The ideal solution would be to play l/r channels combined on both speakers, but I'll settle for playing the left channel through the right speaker. Return the helmet is not an option because of the way they fit.

  I had the same problem, I will use a hardware solution rather.

• two routers E1000 allows to increase the wireless signal

  I have an E1000 router in my office with a cat5 cable going to my room of girls through several doors and some corners. She (recently brought in) also has a router E1000.

  I need to know how to use both routers to increase the signal wireless in his room. I have not tried anything yet.

  The router in my office is configured with the address 192.168.2.1.

  I think that the E1000 does not support the type of internet connection "clipping". Bridge mode would be preferable to use. Be sure to install the latest firmware and see if it does.

  If not, configure it as follows:

  1. connect a computer to the (second) E1000. Open the web interface at http://192.168.1.1/

  2. on the main configuration page, change the address LAN IP of 192.168.1.1 to 192.168.2.2.

  3. on the same page, disable the DHCP server.

  4. save the settings.

  5. unplug the computer and cable cat5 wire in one of the the second E1000 LAN ports. Do not use the internet port of the second E1000!

  Your daughter can use all three remaining LAN ports and the wireless connections.

  For more of a mobile wireless network, the wireless on the two identical (SSID, wireless security, password), don't forget to enable the SSID broadcast, leaving auto channel or use two channels at least 5 apart (e.g. 1 & 6). Customers thus wireless should be able to walk almost invisible between the two access points.

• Need to combine the two VLOOKUP formulas and SO, tried several variations... not getting what I need.

  Hi, thanks for the review, any help is appreciated.

  The problem.

  I am creating a spreadsheet to download information to a database.

  The database is very picky and all the blank cells cannot contain a zero but should be empty because some cells contain the URL of the image.

  A '0' instead of a string with a .jpg extension will throw an error.

  In general, I use an 'IF' statement to achieve this:

  = IF (A1 = "", "", A1)

  It works like a charm. However, I changed the map and now the cells have a 'VLOOPUP' function to draw the other worksheet data.

  If the target cell has no data the host cell will express a '0 '. This will raise errors on the upload.

  I tried to embed the two formulas without success. Is it possible to combine the two forms, or is there another solution to draw the other worksheet data and if the receiving cell has no data to express an empty cell / VIRGIN instead of a '0 '.

  If you need an example let me know.

  I hope it's clear.

  I suspect this is related to MS Office Excel.  If I'm not mistaken, please repost this in the MS Office category for the version that you are using the category at the top of the page tab

• Audition performs the subtraction of two signals?

  I'm just surprised that this feature is not widespread among all sound editing software out there.

  Just as we are able to perform the SUM of 2 channels (i.e. mix), we should be able to perform their SUBTRACTION.

  TIA,

  -Ramon

  Travis,

  It may be late to answer you, but yes you can. Simply to "reverse" a copy of your file wav and "Mix dough/overlap" with the original. The result will be 0.

  Now if you have two different recording, one for an A + B signal and the other with report to subtract B which is a bit more complicated because the two recording received these signals of different paths. This is likely to lead to the difference in frequency response and phase. Lets assume that it is not the case, you will first need to align the two record sources. You can do this in audition 3 using the convolution product, as shown in this video:

  How to make the audio loop perfect using Adobe Audition - YouTube

  Then, reverse the recording with the B signal and 'Paste Mix' together.

  You can do more research on adaptive filtering and the RMS, LMS filter if you want to compensate for the different audio track.

  Good luck!

• Why Apple can't do two systems? First of all, we are protected, and the other is free just like android, but in the style of the iOS and Apple needs a request so we can manage and see new products from an application and do not go on this site!

  Why Apple can't do two systems? First of all, we are protected, and the other is free just like android, but in the style of the iOS and Apple needs a request so we can manage and see new products from an application and do not go on this site!

  and I don't know that if Apple make a system more freely, there no need for any device on Earth but iPhone.

  http://www.Apple.com/feedback/

• I am new to the ethernet communication using labview. I don't have any material. I have two laptop, I need to send and receive data through these 2 portable by using labview. Kindly help me on this.

  I am new to the ethernet communication using labview. I don't have any material. I have two laptop, I need to send and receive data through these 2 portable by using labview. Kindly help me on this.

  Dennis has already said: for a direct PC - PC connection, you need a cross over cable. If you connect through a router or a switch, you use a standard cable.